Translatable pivot latch assembly



Oct. 17, 1967 F. E. POWER 3,347,579

TRANSLATABLE PIVOT LATCH ASSEMBLY Filed Aug 16, 1965 E llll l E Fig. 5

INVENTOR FRANK E. POWER ATTORNEYS United States Patent 3,347,579 TRANSLATABLE PIVOT LATCH ASSEMBLY Frank E. Power, Ashland, Mass., assignor, by mesne assignments, to Minnesota Mining and Manufacturing Company, St. Paul, Minn., a corporation of Delaware Filed Aug. 16, 1965, Ser. No. 479,878 7 Claims. (Cl. 292-122) ABSTRACT OF THE DISCLOSURE A latch assembly for tightly sealing a gasketed door (particularly the door to a vacuum chamber or sterilizer) can be adjusted to compensate for wear or chemical attack of the gasket. A resiliently biased pivoted hook, attached to the chamber and engaging a catch in the door, is adjusted in or out, as necessary.

This invention relates to a novel latch assembly. More particularly this invention relates to an adjustable latch mechanism of particular benefit for maintaining desirable sealing pressure on gasketed closures even after the gaskets have become substantially worn or deformed.

Maintaining satisfactory sealing pressure on closures, especially gasketed closures, has become a common problem as such closures are increasingly used on a wide variety of apparatus in which novel detergents or uncommon chemicals are frequently used. Often the manufacturer of the closure has no way of predicting accurately the range of chemicals to which his gasket will be exposed. This is especially true as new industrial detergents are brought onto the market subjecting gaskets to chemical attack which was not foreseen at the time of their manufacture. Furthermore, gaskets in such apparatus as vacuum chambers and sterilizers may be subjected to chemical attack from a variety of chemical-s and sterilizing agents used therein. In these latter types of apparatus, the problem is particularly severe because the maintenance of a critical pressure difi erential between the inside of the apparatus and the surrounding atmosphere is critical and the leakage around the gasket is intolerable.

Even where the chemical environment is a known factor, the gasketing material thought to be most advantageous for use in a particular environment may be such that it becomes set, i.e., deformed by constant or repeated compression experienced in use.

In all such cases, it becomes most desirable to provide an adjustable latch which can be used to adjust the pressure upon the gasketed closure from time to time as the physical properties or shape of the gasket change.

It is the object of the present invention to provide such a latching means.

In the specification and in the accompanying drawings is described and shown an illustrative embodiment of the present invention; modifications thereof are indicated, but it is to be understood that these are not intended to be exhaustive nor limiting of the invention, but on the contrary are given for purposes of illustration in order that others skilled in the art may fully understand the invention and the manner of applying it in practical applications.

The various objects, aspects, and advantages of the present invention will be more fully understood from a consideration of the specification in conjunction with the accompanying drawings, in which:

FIGURE 1 is a plan view of the latch assembly of the invention;

FIGURE 2 is a rear elevational view of the invention;

FIGURE 3 is a side elevational view, taken partly in section, of a latch assembly showing the relationship of the assembly to a section of a door which can be held closed by the assembly.

With reference to FIGURE 1, there is seen to be a housing 20 having a threaded exterior surface 22 therealong and integral cars 24 at the front end thereof, through which ears 24 screws 28 are inserted to facilitate mounting of the assembly. Two opposed and horizontal slots 30 are cut into housing 20 about midway along the housing. Housing 20 has a recess 32 in which latch member 34 is pivotally mounted on pivot pin 36. Pivot pin 36 is, in turn, slidably mounted in slots 30.

7 On threaded exterior surface 22 are mounted two adjusting and locking members 37 and 38. Each said adjusting and locking member is threaded on the internal diameter thereof for movement along the exterior of housing 20, one on each side of pivot pin 26.

A resilient elastomeric wedge 40 is inserted near the back of housing 20 and provides a support for the rearward portion of latch member 34.

In operation, the latch assembly of the invention is mounted so that the hooked end of the latch member 34 is positioned for cooperative locking action with the catch portion of a door 42 lined with a gasket 44.

In a particular advantageous application for the latch assembly being described the door will be of the type having a resilient gasket to aid its seal on closing a washer, vacuum chamber, sterilizer or the like.

When gasket 44 is new, it will tend to be highly resilient and to maintain its original round shape. In this situation, pivot pin 26 will be advanced in slots 30, to a position relatively close to cars 24 and held securely in place by adjust-and-lock members 37 and 38. However, as gasket 44 begins to age or wear, and, because of the constant pressure of door 42 upon it, takes a different shape, pivot pin 36 will be moved backward toward wedge 40 as far as is required to maintain the desired degree of compression on gasket 44.

As has been emphasized hereinbofore, the illustrative assembly shown in the drawings can be subjected to various modifications in design without avoiding the generic concept of which the illustrated assembly is a particularly advantageous embodiment.

For example, the groove or grooves into which the hook latch member, or other lever member, slidably and pivotally fits could be restricted to grooves in the recess of the housing. In such a case, a lug projecting from the latch member could be used for operable engagement with a single adjust member for movement of the latch member to-and-from in the housing. In this embodiment the lock feature of the illustrated apparatus would either be lost, be achieved by frictional action or alternatively and for example provided by mechanical restraining means also mounted for movement along the housing with the adjust member but which restraining means would be prevented from rotational movement by the housing.

Another such variation on the illustrated assembly would be attaching the biasing means to the latch member directly rather than placing it on the housing.

What is claimed is:

1. An adjustable latch assembly comprising an externally-threaded housing having a recess therein,

a horizontal slot in said housing,

a latch member pivotally and slidably mounted in said slot,

biasing means placed between said latch member and said recess against which said latch may bear and thus be afforded resilient support, and internally-threaded adjusting means mounted on the exterior of said housing for movement therealong, said adjusting means being operably connected with said latch member to provide means formoving said latch back and forth in said housing slot.

2. An assembly as defined in claim 1 wherein said internally-threaded adjusting means consists of at least one internally threaded adjusting member on each side of said pivot pin thereby providing means to both adjust the position of the pivot pin and lock said pin in position.

3. The assembly defined in claim 1 wherein said biasing means is an elastomeric cushion fitted Within said housing recess.

4. An adjustable latch assembly comprising a housing having a recess therein,

a horizontal slot forming an aperture in said housing,

a pivot pin slidably mounted in said slot and projecting therethrough,

a latch member within said housing recess pivotally mounted on said pivot pin,

biasing means placed between said latch member and said recess against which said latch may bear and thus be alforded resilient support, and

adjusting means mounted on'the exterior of said hous ing for movement therealong,

said adjusting means being operably connected with said pivot pin to provide means for moving said latch back andiforth in said horizontal slots.

5. An assembly as defined in claim 4 wherein said internally-threaded adjusting means consists of at least one internally-threaded adjusting member on each side of said pivot pin thereby providing means to both adjust the position of the pivot pin and lock said pin in position.

6. An adjustable latch assesmbly as defined in claim 4 wherein said latch member is a hook-latch.

7. A finely adjustable, translatable pivot pin assembly comprising a housing having a pair of opposed side walls forming a space therebetween for the reception of a lever element, said side walls having opposed pivot pin slots therein and said housing having external threads thereon,

a pivot pin slidable in said pivot pin slots forpivotally supporting said lever element, each opposite terminal end of said pin extending beyond the threaded exterior of saidhousing and a pair of rings, each internally threaded on the threads of said housing and each on an opposite side of said pivot pin whereby said rings may be turned to advance or retract said pivot pin in said pin slots to a desired location therealong and may be threadedly tightened against said pinto lock the same in such desired location.

References Cited UNITED STATES PATENTS 1,276,333 8/1918 Crosta 292-256.75 X 2,265,691 12/1941 Hogg. 2,452,368 10/1948 Gobel 287-62 X MARVIN A. CHAMPION, Primary Examiner.

J. R. MOSES, Examiner. 

1. AN ADJUSTABLE LATCH ASSEMBLY COMPRISING AN EXTERNALLY-THREADED HOUSING HAVING A RECESS THEREIN, A HORIZONTAL SLOT IN SAID HOUSING, A LATCH MEMBER PIVOTALLY AND SLIDABLY MOUNTED IN SAID SLOT, BIASING MEANS PLACED BETWEEN SAID LATCH MEMBER AND SAID RECESS AGAINST WHICH SAID LATCH MAY BEAR AND THUS BE AFFORDED RESILIENT SUPPORT, AND INTERNALLY-THREADED ADJUSTING MEANS MOUNTED ON THE EXTERIOR OF SAID HOUSING FOR MOVEMENT THEREALONG, SAID ADJUSTING MEANS BEING OPERABLY CONNECTED WITH SAID LATCH MEMBER TO PROVIDE MEANS FOR MOVING SAID LATCH BACK AND FORTH IN SAID HOUSING SLOT., 